obama said the american people refuse to be terrorized and praised the actions. >> exhausted runners that kept running to the nearest hospital to give blood and those that stayed to attend to the wounded. first responders who ran into the chaos to save lives, if you want to know who we are, what america is, how we respond to evil, that is it. selfishly, compassionately and unafraid. >> shep: governments around the world are increasing security at public places and landmarks, but there are some major events on the horizon including 30 different marathons. greatest challenge may be in london. tomorrow hundreds of diplomats and dignitaries are expected the funeral of margaret thatcher. on sunday, half a million spectators are expected to line the streets of london for that city's marathon. fox report jonathan hunt live with us. it appears that the london marathon is going to be a a tribute to the victims here in boston? >> the 30,000 expected runners competing in the london marathon on sunday will begin with a 30 seconds moment of silence before they start to tackle that 26.2 mile cours